200950106 六、發明說明： 【發明所屬之技術領域】 本發明，係有關於被使用在光電變換元件中之對電極 、以及具備有該對電極之光電變換元件。 【先前技術】 色素增感太陽電池，係爲由瑞士之Graetzel們所開發 φ 者，並具備有光電變換效率爲高、且製造成本便宜之優點 ，並被作爲新形態之太陽電池而集中注目。 • 色素增感太陽電池之槪略構成，係在透明之導電性的 電極基板上，具備有由二氧化鈦等之氧化物半導體微粒子 (奈米粒子）所成，並具有擔持光增感元件之多孔質膜的 作用電極；和與此作用電極相對向設置之對電極，並在此 些之作用電極與對電極之間，塡充著含有氧化還原對之電 解質者。 G 此種之色素增感太陽電池，係藉由吸收了太陽光等之 入射光的光增感色素而將電子注入至氧化物半導體微粒子 中，並在作用電極與對電極之間產生起電力藉由此，而作 爲將光能量變換爲電力的光電變換元件來起作用。 作爲電解質，一般而言，係使用將Γ/Ι3_等之氧化還 原對溶解在乙腈（acetonitrile )等之有機溶劑中所成的電 解液，除此之外，亦週知有：採用不揮發性之離子液體的 構成、採用將液狀之電解質藉由適當之凝膠化劑來使其凝 膠化並擬固體化之構成、以及採用使用有P型半導體等的 -5- 200950106 固體半導體之構成等。作爲對電極，主要係使用擔持有白 金之導電性的玻璃電極基板、或是金屬基板、或者是多孔 質碳。 碳電極，係爲了提升導電性，而具有多孔質構造。例 如’在專利文獻1中，爲了製作多孔質碳電極，係使用有 包含碳黑、柱狀導電性碳材料與氧化鈦或是導電性氧化物 之電極。 然而，在此碳電極中，由於係包含有氧化鈦或是導電 性氧化物，因此，會有導電性變低之虞。 又，由於係爲了防止短路而在作用電極與對電極之間 具備有由氧化鈦所成之多孔質層，因此，爲了得到多孔質 層，係有必要進行在高溫下之燒結附著工程。在此種高溫 下之燒結附著工程中，會有在所得到之光電變換元件處產 生損傷並使光電變換效率降低之虞。 〔專利文獻1〕日本特開2004-152747號公報 【發明內容】 〔發明所欲解決之課題〕 本發明之目的，係提供一種能夠實現在光電變換效率 爲優良的同時，亦難以產生作用電極與對電極間之短路的 光電變換元件之對電極、以及具備有該對電極之光電變換 元件。 〔用以解決課題之手段〕 -6- 200950106 本發明，係爲一種對電極，其係包含有：由多孔質碳 所成之中間層；和被配置在中間層之其中一面處的絕緣性 之分隔物，多孔質碳，係包含有複數之碳奈米管。 若藉由本發明之對電極，則藉由使用由包含有碳奈米 管之多孔質碳所成的中間層，能夠以低價而得到導電性優 良之對電極。又，藉由在中間層之表層處而如同被膜一般 地被配設的絕緣性之分隔物，能夠對於對電極與其他之電 H 極、亦即是與作用電極直接接觸並短路的情況作抑制。故 而，若藉由本發明之對電極，則除了增設分隔物一事以外 - ，係只要如同先前技術一般地藉由對電極與作用電極來挾 持電解質並進行光電變換元件之組裝即可，因此，在提升 導電性的同時，亦能夠謀求低成本化，並進而亦能夠謀求 連接信賴性之提升。 上述對電極，例如係可作爲光電變換元件之對電極而 使用，該光電變換元件，係至少具備有前述對電極；和與 φ 前述對電極相對向地配置，並具備有擔持著增感色素之氧 化物半導體多孔質層的作用電極；以及被配置在前述對電 極與前述作用電極之間之至少一部份處的電解質。 在上述對電極中，中間層係以通過分隔物而部分性地 露出爲理想。於此情況，係能夠實現具備有更優良之光電 變換效率的光電變換元件。 上述對電極，係亦可更具備有基板，並在基板之其中 一*面處被配置有上述中間層。 在上述對電極中，較理想，複數之碳奈米管的各個之 200950106 長度方向’係對於基板之其中一面而爲略平行。於此情況 ’相較於使複數之碳奈米管的各個之長度方向相對於基板 中之中間層側的面而成爲垂直之情況等，能夠對於其與被 包含在光電變換元件之作用電極間的短路更充分地作抑制 〇 在上述對電極中，較理想，分隔物係爲由聚四氟乙烯 共聚合物所成。聚四氯乙烯共聚合物，其化學性係爲安定 ，且耐藥品性、耐熱性以及電性絕緣性係爲高，因此，若 0 是將其作與電解液相接觸之分隔物而使用，則能夠有效地 抑制對電極與作用電極間之短路。 · 在上述對電極中，碳奈米管，具體而言，係只要爲單 層碳奈米管以及/或是多層碳奈米管即可。 又，本發明，係爲一種光電變換元件，其特徵爲，至 少具備有：上述對電極；和與對電極相對向地配置，並具 備有擔持著增感色素之氧化物半導體多孔質層的作用電極 ;以及被配置在對電極與作用電極之間之至少一部份處的 Ο 電解質，分隔物，係被配置在對電極之中間層與電解層之 間。 若藉由本發明之光電變換元件，則藉由在包含有碳奈 米管之中間層的表層處，將絕緣性之分隔物如同被膜一般 地來作配置，能夠對於具備有多孔質碳層之對電極與作用 電極之間發生短路一事作抑制。又，由於係具備有導電性 爲優良之對電極’因此，成爲能夠提供一種光電變換效率 優良之光電變換元件。 -8- 200950106 〔發明之效果〕 若藉由本發明之對電極，則藉由使用由包含有碳奈米 管之多孔質碳所成的中間層，能夠以低價而得到導電性優 良之對電極。又，藉由在中間層之表層處而如同被膜一般 地被配設的絕緣性之分隔物，能夠對於對電極與其他之電 極、亦即是與作用電極直接接觸並短路的情況作抑制。故 Q 而，由於除了增設分隔物一事以外，係只要如同先前技術 一般地藉由對電極與作用電極來挾持電解質並進行組裝即 . 可，因此，能夠得到一種：在提升導電性的同時，亦能夠 • 謀求低成本化，並進而亦能夠謀求連接信賴性之提升的光 電變換元件用之對電極。其結果，能夠實現一種在光電變 換效率爲優良的同時，亦難以產生作用電極與對電極間之 短路的光電變換元件。 若藉由本發明之光電變換元件，則藉由在包含有碳奈 ❹ 米管之中間層的表層處，將絕緣性之分隔物如同被膜一般 地來作配置，能夠對於具備有多孔質碳層之對電極與作用 電極之間發生短路一事作抑制。又，由於係具備有導電性 爲優良之對電極，因此，成爲能夠提供一種光電變換效率 優良之光電變換元件。 【實施方式】 以下，參考圖面而對於本發明作詳細說明，但是，本 發明係並不被限定於此，在不脫離本發明之主旨的範圍內 -9- 200950106 ，係可進行各種之變更。 圖1，係爲展示本發明之對電極的實施形態之剖面圖 ，圖2，係爲展示圖1之對電極的模式性平面圖，圖3， 係爲圖2中之α的擴大圖，圖4，係爲沿著圖3之M-M線 的剖面圖。如圖1〜圖4中所示一般，對電極10，係槪略 性地由基板11、和被配置在基板11之其中一面11a處的 由多孔質碳所成之中間層1 2、和被配置在中間層1 2之表 層（亦即是其中一面12a)處之絕緣性的分隔物14所構成 0 。中間層12，係包含有複數之碳奈米管13，各個的碳奈 米管13，係使其之長度方向對於基板11之其中一面11a · 而略平行地混合存在並被配置。又，通過分隔物14，中間 ‘ 層12係部分性地又或是局部性地露出。於此，分隔物14 雖係與中間層12之其中一面12a直接接觸，但是，爲了 使異物成爲難以進入、或是成爲不會對中間層12之導電 性造成妨礙，較理想，在分隔物14與中間層1 2之間，係 亦可配置接著材（例如接著用樹脂）等之層。 〇 如此這般，對電極10，由於係具備有包含碳奈米管之 中間層12，因此，係爲低價，且導電性係爲優良。又，藉 由在中間層之表層處而如同被膜一般地被配設的絕緣性之 分隔物14，能夠對於對電極10與其他之電極、亦即是與 作用電極20直接接觸並短路的情況作抑制。故而，除了 增設分隔物14 一事以外，當如同先前技術一般地藉由對 電極10與作用電極20來挾持電解質並進行光電變換元件 50之組裝的情況時，若藉由對電極1〇，則在提升導電性 -10- 200950106 的同時，亦能夠謀求低成本化，並進而亦能夠謀求連接信 賴性之提升。其結果，能夠實現一種在光電變換效率爲優 良的同時，亦難以產生作用電極20與對電極10間之短路 的光電變換元件50。 基板11，係可爲例如鈦基板一般之基板本身即爲由導 電體所成者，亦可爲在例如FTO玻璃基板一般之絕緣基板 的表面上形成了導電膜者。 0 中間層12，係由多孔質碳所成。於此，多孔質碳之 BET法所致的比表面積，通常係爲10〜2000m2/g，較理 * 想係爲50〜1 000m2/ g。中間層12之厚度，係可考慮所 * 需要之導電性，而適宜地作調節，但是，例如，係爲5/ίΐη 以上、100/zm以下。此多孔質碳，係由複數之碳奈米管 13所構成。此碳奈米管13，係以使其之長度方向與基板 11之其中一面11a或是中間層12之其中一面12a略平行 的方式而被配置。因此，相較於使複數之碳奈米管13的 © 各個之長度方向相對於基板11中之中間層12側的其中一 面11a或是中間層12之其中一面12a而成爲垂直之情況 ，等，能夠對於其與被包含在光電變換元件50之作用電極 20間的短路更充分地作抑制。進而，碳奈米管13，係除 了以使其之長度方向與基板11之其中一面11a或是中間 層12之其中一面12a略平行的方式而被配置以外，亦混 合存在地被作隨機配置。亦即是，在基板11之其中一面 11a內，長度方向係朝向各種之方向，而該種碳奈米管13 係混合存在。 -11 - 200950106 碳奈米管13，係具備有：碳六員環相連結之石墨的單 層（石墨片，Graphene sheet)被形成爲圓筒形狀或是圓 錐梯形狀的筒狀之構造。又，直徑係爲0.7〜50nm左右， 長度係爲數ym，且爲具備有中空構造之縱橫比非常大的 材料。於此，縱橫比，係代表相對於直徑之長度的比，較 理想，係爲10〜20000，更理想，係爲100〜1 0000。若是 縱橫比未滿1 〇，則比表面積係有變小的傾向，若是縱橫比 超過2000，則碳奈米管13係成爲容易從分隔物14而突出 q 〇 碳奈米管1 3，作爲電性性質，係依存於直徑或是空間 . 螺旋特性（chirality )而顯示金屬〜半導體性之性質，又 · ，作爲機械性之性質，係具備有大的楊格率，且亦具備有 可經由曲度（buckling )而將應力緩和的特徵。進而，碳 奈米管13，由於並不具有懸鍵，故係爲化學性安定，並且 由於係爲由低價之碳化氫所合成，因此，在能夠大量生產 的同時，亦能夠謀求低成本化。 © 多孔質碳，只要是包含有碳奈米管者即可。故而，多 孔質碳，係可爲由複數之單層碳奈米管所成者，亦可爲由 複數之多層碳奈米管所成者。又，亦可爲由複數之單層碳 奈米管與複數之多層碳奈米管混合而成者。當將單層之碳 奈米管與多層之碳奈米管混合使用的情況時，對於混合之 比例，係並未作特別限定，可考慮所適用之光電變換元件 或光電變換效率等，而適宜地調節並作混合。 當碳奈米管13係爲單層，亦即是石墨片係爲1層的 -12- 200950106 情況時，此碳奈米管13之直徑係爲例如〇.5nm〜10nm， 又，長度係爲例如10nm〜1/zm。 當碳奈米管13係爲多層，亦即是石墨片係爲多層的 情況時，此碳奈米管13之直徑係爲例如lnm〜lOOiim，又 ，長度係爲例如50ηιη〜5〇μιη。 此種碳奈米管13，係可藉由週知的方法來製作，作爲 該方法，例如係可使用化學氣相法（CVD法）、電弧法、 0 雷射剝蝕（Laser Ablation )法等。 例如，如同日本特開2 0 0 1 -2 2 0 6 74號公報中所記載一 般，在基板11之其中一面11a上將鎳、鈷、鐵等之金屬 藉由濺鍍或是蒸鍍來成膜，而後，在惰性氣體氛圍、氫氛 圍或是真空中，以較理想爲500〜900°C之溫度來作1〜60 分鐘的加熱，接著，將乙炔、乙烯等之碳氫氣體或是乙醇 氣體作爲原料來使用’並使用一般之化學氣相法（CVD ) 來進行成膜。藉由此，能夠在基板11上使直徑5〜75nm Q 、長度1〜500/zm的碳奈米管作成長。 碳奈米管之長度或粗細（直徑），係在使用CVD法 而形成碳奈米管時，經由對例如溫度或時間作控制，而能 夠進行控制。 作爲在本發明中所使用之碳奈米管1 3，較理想，係爲 直徑0.5〜100nm、長度10nm〜50ym者。 絕緣性之分隔物14，係如圖3及圖4中所示一般，在 中間層12與電解質相接之一面12a側處，以將複數之碳 奈米管11作被覆一般的狀態而被配置。又，以使通過分 -13- 200950106 隔物14而中間層12係具備有部分性地又或是局部性地露 出之部分的方式而作配置。此分隔物14,係爲對於本發明 之對電極1 0與作用電極20相接觸並引起短路一事作抑制 者。 分隔物14，較理想，係由在化學性上係爲安定且耐藥 品性、耐熱性以及電性絕緣性爲高之聚四氟乙烯共聚合物 所成。聚四氯乙烯共聚合物，其化學性係爲安定，且耐藥 品性、耐熱性以及電性絕緣性係爲高，因此，若是將其作 q 與電解液3 0相接觸之分隔物而使用，則能夠有效地抑制 與光電變換元件50的作用電極20間之短路。作爲聚四氟 乙烯共聚合物，係可使用市面上所販賣者，例如，係可列 舉出以 POLYFLON ' TEFLON (登記商標）、FLUON、 HALON、HOSTAFLON等之商品名所販賣者。 圖5，係爲對於具備有本發明之對電極10的光電變換 元件50作模式性展示的剖面圖。光電變換元件50，其槪 略構成，係包含有：由基板11以及被配置在基板11之其 © 中一面11a處的由多孔質碳所成之中間層12而構成的對 電極10;和被與中間層12作對向配置，並具備有擔持有 增感色素之氧化物半導體多孔質層23的作用電極20 ;和 被配置在對電極10以及作用電極20之間之至少一部份處 的電解質30。又，對於將電解質30藉由作用電極20與對 電極10所挾持而成之層積體，將其之外週部經由密封構 件來作接著並一體化，而構成光電變換元件50。 藉由在中間層1 2之與電解質3 0相接的一面1 2a側處 -14- 200950106 配置分隔物14，而對於對電極10與作用fl 短路一事作抑制。，若是作用電極20與築 距離變大，則胞內之溶液的電阻成分係增 性係降低。故而，分隔物14之厚度，係以 50/zm以下爲理想，更理想，係爲1/zml； 。藉由此，能夠對於作用電極20與對電棰 作更進一步的抑制，同時，能夠得到光電 φ 光電變換元件50。 作用電極20，其槪略構成，係包含， 及被形成在其之主面上的透明導電膜22、 素之多孔質氧化物半導體層23。 作爲基材21，係使用有由光透過性之 ，例如玻璃、聚對苯二甲酸乙二酯、聚碳 ，只要是通常作爲光電變換元件之透明基 可以使用任意之物。基材21，係從該些之 φ 解液之耐性等而適宜作選擇。又，作爲基4 ，係以儘可能地選擇光透過性優良的基板 過率90%以上之基板爲更理想。 透明導電膜22，係爲爲了對於基材2 而被形成在基材之其中一面上的薄膜。爲 明性造成顯著損害的構造，透明導電膜22 電性金屬氧化物所成之薄膜爲理想。 作爲形成透明導電膜22之導電性金 ，係使用有錫添加氧化銦（ITO )、氟添 I極20相接觸並 f電極1 〇之間的 加，胞之發電特 I 0.1 y m 以上、 2上20/zm以下 i 1 0之間的短路 變換效率優良之 『：基材21、以 和擔持有增感色 素材所成的基板 酸酯、聚醚碾等 材所使用者，則 中而考慮對於電 才21，在用途上 爲理想，又以透 1賦予導電性， 了設爲不會對透 ，係以身爲由導 屬氧化物，例如 加氧化錫（FT Ο -15- 200950106 )、氧化錫（Sn02 )等。此些之中，從成膜爲溶液且製造 成本係爲低價的觀點來看，係以IT Ο、FTO爲理想。又， 透明導電膜22 ’係以僅由ITO所成之單層的膜、或是在 由ITO所成之膜上層積有由FTO所成之膜而成的層積膜 爲理想® 藉由將透明導電膜22設爲僅由FTO所成之單層的膜 、或是設爲在由ITO所成之膜上層積由FTO所成之膜而 成的層積膜，能夠構成一種··在可視區域中之光的吸收量 _ 係爲少，且導電率爲高之透明導電性基板。 多孔質氧化物半導體層23，係被設置在透明導電膜 22之上，於其之表面處，係擔持有增感色素。作爲形成多 孔質氧化物半導體層23之半導體，係並未特別限制，通 常，只要是被使用於形成光電變換元件之多孔質氧化物半 導體者，則可以使用任意之物。作爲此種半導體，例如， 係可使用氧化鈦（Ti〇2 )、氧化錫（Sn02 )、氧化鎢（ W〇3)、氧化鋅（ZnO)、氧化鈮（Nb205 )等。 ❹ 作爲形成多孔質氧化物半導體層23之方法，例如， 係可在將市面販售之氧化物半導體微粒子分散在所期望之 分散媒體中後所得的分散液或是在能夠藉由溶膠法而調製 的膠體（colloid)溶液中，因應於需要而添加所期望之添 加劑’而後，藉由網版印刷法、噴墨印刷法、滾輪塗布法 、刮刀法、噴霧塗布法等之週知的塗布方法來作塗布，之 後’將此聚合物微粒藉由加熱處理或化學處理而除去，來 使其形成空隙並多孔質化之方法等。 -16- 200950106 作爲增感色素，係可適用在將配位子中包含有聯吡啶 (bipyridine)構造、三聯耻陡（terpyridine)構造等的釕 錯合物、口卜啉（Porphyrin )、鈦花青（Phthalocyanine)等 之含金屬錯合物、曙紅（eosin)、玫瑰紅（Rhodamine) 、部花青素（Merocyanine )等的有機色素等，只要是展 示有適合於用途、所使用之半導體的舉動者，則可從此些 之中不受到特別限制地來作選擇。 〇 電解質30，係使用在多孔質氧化物半導體層23內含 浸電解液後所成者、或是使用在使多孔質氧化物半導體層 23內含浸電解液後，再對此電解液使用適當之凝膠化劑而 凝膠化（擬固體化），而與多孔質氧化物半導體層23 — 體化地形成者、或者是使用包含有離子液體、氧化物半導 體粒子以及導電性粒子之凝膠狀的電解質。 作爲上述電解液，係使用在碳酸乙烯脂或甲氧基乙腈 等之有機溶媒中溶解了碘、碘化物離子、第三丁基吡啶等 Φ 之電解質成分所成者。 作爲在將此電解液凝膠化時所使用之凝膠化劑，係可 列舉有聚二氟亞乙烯、聚氧化乙烯衍生物、胺基酸衍生物 等。 作爲上述離子液體，雖並未特別限定，但是，係可列 ：在室溫下係爲液體，而將具備有被四級化之氮原子 的化合物作了陽離子化或陰離子化後的常溫溶融性鹽。 作爲常溫溶融性鹽之陽離子，係可列舉有四級化咪唑 衍生物 '四級化吡啶衍生物、四級化銨衍生物等。 -17- 200950106 作爲常溫溶融性鹽之陰離子，係可列舉有：BF4·、 PF6_、F(HF)，、雙（三氟甲基磺酰）亞胺、碘化物離子等。 作爲離子液體之具體例，係可列舉有由四級化咪唑系 陽離子與碘化物離子或是雙（三氟甲基磺酰）亞胺等所成的 鹽類。 作爲上述氧化物半導體粒子，對於物質之種類或是粒 子尺寸雖並未特別限定，但是，係使用以離子液體爲主體 一般之與電解液間的混合性優良而將此電解液作了凝膠化 Q 後者。又，氧化物半導體粒子，係必須要不會使電解質之 半導電性降低，且對於被包含在電解質中之其他的共存成 分而化學性之安定性爲優良。特別是，係以就算是在電解 質係包含有碘/碘化物離子、或是溴/溴化物離子等之氧 化還原對的情況時，氧化物半導體粒子亦不會產生由於氧 化反應所致之劣化者爲理想。 作爲此種氧化物半導體粒子，係以從由Ti02、Sn02 、WO3、Ζ η Ο ' Ν b 2 Ο 5 ' IΠ2 Ο 3 ' Zr〇2、Τ a 2 Ο 5 ' L a2 Ο 3 '[Technical Field] The present invention relates to a counter electrode used in a photoelectric conversion element, and a photoelectric conversion element including the pair of electrodes. [Prior Art] The dye-sensitized solar cell is developed by the Graetzel of Switzerland, and has the advantages of high photoelectric conversion efficiency and low manufacturing cost, and has been focused on as a new form of solar cell. • The sensitization of the dye-sensitized solar cell is formed on a transparent conductive electrode substrate, and is made of oxide semiconductor fine particles (nanoparticles) such as titanium dioxide, and has a porous optical sensitizing element. a working electrode of the plasma membrane; and a counter electrode disposed opposite to the working electrode, and between the working electrode and the counter electrode, the electrolyte containing the redox pair is filled. G such a dye-sensitized solar cell injects electrons into the oxide semiconductor fine particles by a light sensitizing dye that absorbs incident light such as sunlight, and generates electricity between the working electrode and the counter electrode. Thereby, it functions as a photoelectric conversion element that converts optical energy into electric power. As the electrolyte, generally, an electrolytic solution obtained by dissolving a redox pair of ruthenium/iridium or the like in an organic solvent such as acetonitrile is used, and it is also known that non-volatile is used. The composition of the ionic liquid is a composition in which a liquid electrolyte is gelled and solidified by a suitable gelling agent, and a composition of a -5-200950106 solid semiconductor using a P-type semiconductor or the like is used. Wait. As the counter electrode, a glass electrode substrate carrying platinum conductivity, a metal substrate, or porous carbon is mainly used. The carbon electrode has a porous structure in order to improve conductivity. For example, in Patent Document 1, an electrode including carbon black, a columnar conductive carbon material, titanium oxide or a conductive oxide is used in order to produce a porous carbon electrode. However, in this carbon electrode, since titanium oxide or a conductive oxide is contained, conductivity is lowered. Further, since a porous layer made of titanium oxide is provided between the working electrode and the counter electrode in order to prevent short-circuiting, it is necessary to perform a sintering adhesion process at a high temperature in order to obtain a porous layer. In such a sintering adhesion process at such a high temperature, damage occurs in the obtained photoelectric conversion element and the photoelectric conversion efficiency is lowered. [Problem to be Solved by the Invention] It is an object of the present invention to provide an effect that the photoelectric conversion efficiency is excellent and that it is difficult to generate an active electrode and A counter electrode of a photoelectric conversion element that short-circuits between electrodes, and a photoelectric conversion element including the pair of electrodes. [Means for Solving the Problem] -6- 200950106 The present invention is a counter electrode comprising: an intermediate layer made of porous carbon; and an insulating layer disposed at one of the intermediate layers The separator, porous carbon, contains a plurality of carbon nanotubes. According to the counter electrode of the present invention, by using an intermediate layer made of porous carbon containing a carbon nanotube, it is possible to obtain a counter electrode having excellent conductivity at a low cost. Further, by the insulating separator which is disposed in the surface layer of the intermediate layer as a film, it is possible to suppress the electrode and other electric H electrodes, that is, the direct contact and short circuit with the working electrode. . Therefore, if the counter electrode of the present invention is used in addition to the addition of the separator, it is only necessary to hold the electrolyte and perform the assembly of the photoelectric conversion element by the counter electrode and the working electrode as in the prior art. At the same time as the conductivity, it is also possible to reduce the cost, and further, it is possible to improve the connection reliability. The counter electrode can be used, for example, as a counter electrode of a photoelectric conversion element, and the photoelectric conversion element includes at least the counter electrode; and is disposed opposite to the counter electrode of φ, and is provided with a sensitizing dye a working electrode of the oxide semiconductor porous layer; and an electrolyte disposed at at least a portion between the counter electrode and the working electrode. In the above counter electrode, it is preferable that the intermediate layer is partially exposed by the separator. In this case, it is possible to realize a photoelectric conversion element having more excellent photoelectric conversion efficiency. The counter electrode may further include a substrate, and the intermediate layer may be disposed on one of the sides of the substrate. In the above counter electrode, it is preferable that each of the plurality of carbon nanotubes has a longitudinal direction of 200950106 which is slightly parallel to one side of the substrate. In this case, the length direction of each of the plurality of carbon nanotubes is perpendicular to the surface on the intermediate layer side in the substrate, and the like, and the electrode between the electrodes of the photoelectric conversion element can be included. The short circuit is more sufficiently suppressed. In the above counter electrode, it is preferred that the separator be made of a polytetrafluoroethylene copolymer. The polytetrachloroethylene copolymer is chemically stable, and has high chemical resistance, heat resistance, and electrical insulation. Therefore, if 0 is a separator that is in contact with the electrolyte, Therefore, the short circuit between the counter electrode and the working electrode can be effectively suppressed. In the above counter electrode, the carbon nanotubes, specifically, a single-layer carbon nanotube and/or a multilayer carbon nanotube. Furthermore, the present invention provides a photoelectric conversion element comprising: at least the counter electrode; and an oxide semiconductor porous layer having a sensitizing dye disposed in a direction opposite to the counter electrode; a working electrode; and a ruthenium electrolyte disposed at at least a portion between the counter electrode and the working electrode, the separator being disposed between the intermediate layer of the counter electrode and the electrolytic layer. According to the photoelectric conversion element of the present invention, by providing the insulating spacer as a film in the surface layer of the intermediate layer containing the carbon nanotube, it is possible to have a pair having a porous carbon layer. A short circuit between the electrode and the working electrode is suppressed. In addition, since the counter electrode having excellent conductivity is provided, it is possible to provide a photoelectric conversion element excellent in photoelectric conversion efficiency. -8- 200950106 [Effects of the Invention] According to the counter electrode of the present invention, by using an intermediate layer made of porous carbon containing a carbon nanotube, it is possible to obtain a counter electrode having excellent conductivity at a low cost. . Further, by the insulating separator which is disposed in the surface layer of the intermediate layer as a film, it is possible to suppress the electrode and other electrodes, that is, the direct contact with the working electrode and short-circuit. Therefore, in addition to the addition of the separator, it is only necessary to hold the electrolyte and assemble the electrode by the counter electrode and the working electrode as in the prior art. Therefore, it is possible to obtain a type: while improving conductivity, It is possible to reduce the cost and further improve the reliability of the counter electrode for the photoelectric conversion element. As a result, it is possible to realize a photoelectric conversion element in which the photoelectric conversion efficiency is excellent and it is difficult to cause a short circuit between the working electrode and the counter electrode. According to the photoelectric conversion element of the present invention, the insulating spacer can be disposed as a film in the surface layer of the intermediate layer containing the carbon nanotube, and the porous carbon layer can be provided. The short circuit between the counter electrode and the working electrode is suppressed. Further, since the counter electrode having excellent conductivity is provided, it is possible to provide a photoelectric conversion element excellent in photoelectric conversion efficiency. [Embodiment] The present invention will be described in detail below with reference to the drawings. However, the present invention is not limited thereto, and various modifications can be made without departing from the scope of the present invention. . 1 is a cross-sectional view showing an embodiment of a counter electrode of the present invention, FIG. 2 is a schematic plan view showing a counter electrode of FIG. 1, and FIG. 3 is an enlarged view of α in FIG. , is a cross-sectional view along the MM line of FIG. As shown in FIG. 1 to FIG. 4, the counter electrode 10 is slightly composed of a substrate 11, and an intermediate layer 12 made of porous carbon disposed on one side 11a of the substrate 11, and The insulating separator 14 disposed at the surface layer (i.e., one of the faces 12a) of the intermediate layer 12 constitutes 0. The intermediate layer 12 is composed of a plurality of carbon nanotubes 13 each of which is disposed such that its longitudinal direction is slightly parallel to one side 11a of the substrate 11 and is disposed. Also, through the partition 14, the intermediate layer 12 is partially or partially exposed. Here, the separator 14 is in direct contact with one of the one faces 12a of the intermediate layer 12. However, in order to make the foreign matter difficult to enter or to prevent the conductivity of the intermediate layer 12 from being impeded, it is preferable that the separator 14 Between the intermediate layer 12 and the intermediate layer 12, a layer of a backing material (for example, a resin) may be disposed. In this manner, since the counter electrode 10 is provided with the intermediate layer 12 including the carbon nanotubes, it is inexpensive and excellent in electrical conductivity. Further, by the insulating spacer 14 which is disposed as a film in the surface layer of the intermediate layer, it is possible to make the counter electrode 10 and other electrodes, that is, the direct contact with the working electrode 20 and short-circuit. inhibition. Therefore, in addition to the addition of the separator 14, when the electrolyte is held by the counter electrode 10 and the working electrode 20 as in the prior art, and the assembly of the photoelectric conversion element 50 is performed, if the counter electrode 1 is used, When the conductivity is increased -10, 2009, the cost can be reduced, and the reliability of the connection can be improved. As a result, it is possible to realize a photoelectric conversion element 50 in which the photoelectric conversion efficiency is excellent and it is difficult to cause a short circuit between the working electrode 20 and the counter electrode 10. The substrate 11 may be, for example, a titanium substrate. The substrate itself is formed of a conductive material, or a conductive film may be formed on the surface of an insulating substrate such as a FTO glass substrate. 0 The intermediate layer 12 is made of porous carbon. Here, the specific surface area due to the BET method of porous carbon is usually 10 to 2000 m 2 /g, which is equivalent to 50 to 1 000 m 2 /g. The thickness of the intermediate layer 12 is appropriately adjusted in consideration of the required conductivity, but is, for example, 5/ίΐη or more and 100/zm or less. This porous carbon is composed of a plurality of carbon nanotubes 13 . The carbon nanotube 13 is disposed such that its longitudinal direction is slightly parallel to one of the one surface 11a of the substrate 11 or one of the intermediate layers 12a. Therefore, compared with the case where the length direction of each of the plurality of carbon nanotubes 13 is perpendicular to one of the one side 11a of the intermediate layer 12 side of the substrate 11 or one of the intermediate layers 12, etc., It is possible to more sufficiently suppress the short circuit between the working electrode 20 and the working electrode 20 included in the photoelectric conversion element 50. Further, the carbon nanotubes 13 are arranged such that their longitudinal directions are slightly parallel to one of the one surface 11a of the substrate 11 or one of the intermediate layers 12a, and are also randomly arranged. That is, in one of the faces 11a of the substrate 11, the longitudinal direction is oriented in various directions, and the carbon nanotubes 13 are mixed. -11 - 200950106 The carbon nanotube 13 is a tubular structure in which a single layer (graphite sheet) of graphite having a carbon six-membered ring phase is formed into a cylindrical shape or a circular pyramid shape. Further, the diameter is about 0.7 to 50 nm, the length is several ym, and the material having a hollow structure has a very large aspect ratio. Here, the aspect ratio represents a ratio with respect to the length of the diameter, and is preferably 10 to 20,000, more preferably 100 to 10,000. If the aspect ratio is less than 1 〇, the specific surface area tends to be small. If the aspect ratio exceeds 2,000, the carbon nanotube 13 is likely to protrude from the separator 14 and the carbon nanotube tube 13 is easily formed. Sexual nature depends on the diameter or space. The helicity shows the nature of the metal~semiconductor. Moreover, as a mechanical property, it has a large Younger rate and is also available. A characteristic of buckling that moderates stress. Further, since the carbon nanotube 13 does not have a dangling bond, it is chemically stable, and since it is synthesized from a low-cost hydrocarbon, it can be mass-produced and can also be reduced in cost. . © Porous carbon, as long as it contains carbon nanotubes. Therefore, the porous carbon may be composed of a plurality of single-layer carbon nanotubes or a plurality of carbon nanotubes. Further, it may be a mixture of a plurality of single-layer carbon nanotubes and a plurality of layers of carbon nanotubes. When a single-layer carbon nanotube is used in combination with a plurality of carbon nanotubes, the ratio of mixing is not particularly limited, and may be considered in consideration of applicable photoelectric conversion elements or photoelectric conversion efficiency. Adjust and mix. When the carbon nanotube 13 is a single layer, that is, the case where the graphite sheet is one layer of -12-200950106, the diameter of the carbon nanotube 13 is, for example, 〇5 nm to 10 nm, and the length is For example, 10 nm to 1/zm. When the carbon nanotubes 13 are multi-layered, that is, in the case where the graphite sheets are multi-layered, the diameter of the carbon nanotubes 13 is, for example, 1 nm to 100 μm, and the length is, for example, 50 ηηη to 5 〇 μηη. Such a carbon nanotube 13 can be produced by a known method, and as the method, for example, a chemical vapor phase method (CVD method), an arc method, a zero laser ablation (Laser Ablation) method, or the like can be used. For example, a metal such as nickel, cobalt or iron is formed by sputtering or vapor deposition on one of the surfaces 11a of the substrate 11 as described in JP-A-2000-2002. The film is then heated in an inert gas atmosphere, a hydrogen atmosphere or a vacuum at a temperature of preferably 500 to 900 ° C for 1 to 60 minutes, followed by a hydrocarbon gas such as acetylene or ethylene or ethanol. The gas is used as a raw material and formed by a general chemical vapor phase (CVD) method. Thereby, a carbon nanotube having a diameter of 5 to 75 nm Q and a length of 1 to 500/zm can be grown on the substrate 11. The length or thickness (diameter) of the carbon nanotubes can be controlled by controlling, for example, temperature or time when the carbon nanotubes are formed by the CVD method. The carbon nanotube 13 used in the present invention is preferably a diameter of 0.5 to 100 nm and a length of 10 nm to 50 μm. The insulating separator 14 is generally disposed as shown in Figs. 3 and 4, in a state in which the intermediate layer 12 is in contact with the electrolyte on one side 12a side, in a state in which a plurality of carbon nanotubes 11 are covered as a general state. . Further, the intermediate layer 12 is disposed so as to be partially or partially exposed by the partition 14 - 200950106. This separator 14 is intended to suppress the contact of the counter electrode 10 of the present invention with the working electrode 20 and cause a short circuit. The separator 14 is preferably made of a polytetrafluoroethylene copolymer which is chemically stable and has high resistance to chemicals, heat resistance and electrical insulation. The polytetrachloroethylene copolymer has a chemical stability and is high in chemical resistance, heat resistance, and electrical insulation. Therefore, it is used as a separator in which q is in contact with the electrolyte 30. Therefore, the short circuit with the working electrode 20 of the photoelectric conversion element 50 can be effectively suppressed. As the polytetrafluoroethylene copolymer, those which are commercially available, for example, those sold under the trade names of POLYFLON 'TEFLON (registered trademark), FLUON, HALON, HOSTAFLON, and the like can be used. Fig. 5 is a cross-sectional view schematically showing a photoelectric conversion element 50 having the counter electrode 10 of the present invention. The photoelectric conversion element 50 is a schematic configuration including a counter electrode 10 composed of a substrate 11 and an intermediate layer 12 made of porous carbon disposed on one surface 11a of the substrate 11; The counter electrode 12 is disposed opposite to the intermediate layer 12, and includes a working electrode 20 having an oxide semiconductor porous layer 23 holding a sensitizing dye; and at least a portion disposed between the counter electrode 10 and the working electrode 20 Electrolyte 30. In addition, the laminated body in which the electrolyte 30 is held by the working electrode 20 and the counter electrode 10 is bonded and integrated via the sealing member to form the photoelectric conversion element 50. The partition 14 is disposed at the side of the intermediate layer 12 which is in contact with the electrolyte 30, at the side of the side 1 2a, -14-200950106, and the short-circuit of the counter electrode 10 and the action fl is suppressed. When the distance between the working electrode 20 and the building is increased, the resistance component of the intracellular solution is decreased. Therefore, the thickness of the separator 14 is preferably 50/zm or less, more preferably 1/zml; Thereby, the working electrode 20 and the counter electrode can be further suppressed, and the photoelectric φ photoelectric conversion element 50 can be obtained. The working electrode 20 is composed of a transparent conductive film 22 and a porous oxide semiconductor layer 23 which are formed on the main surface thereof. As the substrate 21, for example, glass, polyethylene terephthalate or polycarb is used, and any material can be used as long as it is a transparent group which is usually used as a photoelectric conversion element. The substrate 21 is suitably selected from the resistance of the φ solution and the like. Further, as the base 4, it is more preferable to select a substrate having an excellent substrate transmittance of 90% or more as much as possible. The transparent conductive film 22 is a film formed on one side of the substrate for the substrate 2. A thin film made of an electrically conductive metal oxide of the transparent conductive film 22 is ideal for a structure which causes significant damage to the display. As the conductive gold forming the transparent conductive film 22, tin is added with indium oxide (ITO), fluorine is added to the electrode 20, and f is added between the electrodes 1 and 〇, and the generation of the cells is particularly 0.1 0.1 μm or more. "The short-circuit conversion efficiency between 20/zm and below i 1 0 is excellent": the substrate 21, the substrate acid ester and the polyether-rolled material which are made of the dye-sensitive material are considered. For electric power 21, it is ideal for use, and it imparts conductivity by transmitting through it, and it is set as a conductive oxide, such as tin oxide (FT Ο -15 - 200950106 ). Tin oxide (Sn02) and the like. Among these, from the viewpoint that the film formation is a solution and the manufacturing cost is low, IT Ο and FTO are preferable. Further, the transparent conductive film 22' is preferably a single layer film made of ITO or a laminated film formed by laminating a film made of ITO on a film made of ITO. The transparent conductive film 22 is a single layer film formed of only FTO or a laminated film formed by laminating a film made of FTO on a film made of ITO, and can be configured to be visible. The amount of absorption of light in the region is a transparent conductive substrate having a small conductivity and a high conductivity. The porous oxide semiconductor layer 23 is provided on the transparent conductive film 22, and a sensitizing dye is held on the surface thereof. The semiconductor forming the porous oxide semiconductor layer 23 is not particularly limited, and any material can be used as long as it is used for forming a porous oxide semiconductor of a photoelectric conversion element. As such a semiconductor, for example, titanium oxide (Ti〇2), tin oxide (Sn02), tungsten oxide (W〇3), zinc oxide (ZnO), niobium oxide (Nb205), or the like can be used. ❹ As a method of forming the porous oxide semiconductor layer 23, for example, a dispersion obtained by dispersing commercially available oxide semiconductor fine particles in a desired dispersion medium can be prepared by a sol method. In the colloid solution, a desired additive is added as needed, and then a known coating method such as a screen printing method, an inkjet printing method, a roll coating method, a doctor blade method, or a spray coating method is used. After coating, the method of removing the polymer fine particles by heat treatment or chemical treatment to form a void and making it porous is used. -16- 200950106 As a sensitizing dye, it is applicable to a ruthenium complex containing a bipyridine structure or a terpyridine structure, a Porphyrin, and a titanium flower. An organic dye such as a metal-containing complex such as Phthalocyanine, eosin, Rhodamine, or Merocyanine, etc., as long as it exhibits a semiconductor suitable for use and use. The mover can choose from among these without special restrictions. The ruthenium electrolyte 30 is obtained by impregnating an electrolyte solution in the porous oxide semiconductor layer 23 or by impregnating the electrolyte in the porous oxide semiconductor layer 23, and then using the appropriate condensate for the electrolyte. Gelatinized by a gelling agent (solidified), formed integrally with the porous oxide semiconductor layer 23, or gelled using an ionic liquid, oxide semiconductor particles, and conductive particles. Electrolyte. As the electrolyte solution, an electrolyte component in which Φ such as iodine, iodide ion or tributylpyridine is dissolved in an organic solvent such as ethylene carbonate or methoxyacetonitrile is used. The gelling agent to be used in the gelation of the electrolytic solution may, for example, be polydivinylene vinylene, a polyoxyethylene derivative or an amino acid derivative. The ionic liquid is not particularly limited, but may be a room temperature meltable property obtained by cationizing or anionizing a compound having a nitrogen atom which is quaternized at room temperature. salt. Examples of the cation of the room temperature molten salt include a quaternary imidazole derivative, a quaternized pyridine derivative, and a quaternized ammonium derivative. -17- 200950106 Examples of the anion of the room temperature molten salt include BF4·, PF6_, F(HF), bis(trifluoromethylsulfonyl)imide, and iodide ion. Specific examples of the ionic liquid include salts composed of a quaternary imidazole-based cation, an iodide ion or bis(trifluoromethylsulfonyl)imide. The oxide semiconductor particles are not particularly limited in terms of the kind of the substance or the particle size, but the electrolyte is gelled by using an ionic liquid as a main component and having excellent compatibility with the electrolyte. Q The latter. Further, the oxide semiconductor particles are required to have no deterioration in the semiconductivity of the electrolyte, and are excellent in chemical stability with respect to other coexisting components contained in the electrolyte. In particular, even in the case where the electrolyte contains an iodine/iodide ion or a redox pair such as a bromine/bromide ion, the oxide semiconductor particles do not cause deterioration due to an oxidation reaction. Ideal. As such an oxide semiconductor particle, it is derived from TiO 2 , Sn02 , WO 3 , η η Ν Ν b 2 Ο 5 ' I Π 2 Ο 3 ' Zr 〇 2 Τ a 2 Ο 5 ' L a2 Ο 3 '
SrTi03、Υ203、Η02Ο3、Bi2〇3、Ce02、Α1203 所成之群中 所選擇的1種或是2種以上之混合物爲理想，又以二氧化 鈦微粒子（奈米粒子）爲特別理想。此二氧化鈦之平均粒 徑，係以2nm〜lOOOnm左右爲理想。 作爲上述導電性微粒子，係使用導電體或半導體等之 具有導電性的粒子。 此導電性粒子之比電阻的範圍，較理想係爲1.0x1 0·2 Ω · cm以下，更理想係爲1·〇χ1〇_3Ω · cm以下。又，對 -18- 200950106 於導電性粒子之種類或是粒子尺寸雖並未特別限定，但是 ，係使用以離子液體爲主體一般之與電解液間的混合性優 良而將此電解液作了凝膠化後者。進而，導電性粒子，係 必須要不會在電解質中形成氧化分隔物（絕緣分隔物）等 並使導電性降低，且對於被包含在電解質中之其他的共存 成分而化學性之安定性爲優良。特別是，作爲導電性粒子 ，係以就算是在電解質係包含有碘/碘化物離子、或是溴 φ /溴化物離子等之氧化還原對的情況時，亦不會產生由於 氧化反應所致之劣化者爲理想。 作爲此種導電性微粒子，係可列舉有以碳爲主體之物 質，作爲具體例，係可例示有碳奈米管、碳纖維、碳黑等 之粒子。此些之物質的製造方法係均爲週知，又，亦可使 用市面上所販賣者。 密封構件40，只要是對於構成對電極10之基板11或 對於構成作用電極20之基材21而具有優良之接著性者， Θ 則並不被特別限定，作爲構成密封構件40之材料，例如 ’係可列舉有：離子聚合物、乙烯-醋酸乙烯無水共聚物 、乙烯-甲基丙烯酸共聚物、乙烯-乙烯醇共聚物、紫外線 硬化樹脂、以及乙烯醇共聚物等的樹脂。另外，密封構件 40係可僅藉由樹脂來構成，亦可藉由樹脂與無機塡充物來 構成。作爲上述樹脂，具體而言，係可列舉有：HIMILAN (三井杜邦化學公司製）、NUCREL (三井杜邦化學公司 製）等。 本發明，係並不被限定於上述實施形態。例如，在上 -19- 200950106 述實施形態中，對電極10雖係具備有基板H，但是，係 並非一定要包含有基板11。例如，當能夠在基材上塗布中 間層12，而後，從基材來作爲自立膜而分離的情況時，對 電極，係亦可由中間層12與分隔物14而構成。 又’在上述實施形態中，於中間層12處，各個的碳 奈米管13，係使其之長度方向對於基板1 1之其中一面 11a而略平行地混合存在並被配置，但是，各個的碳奈米 管13’係亦可並非一定要使其之長度方向對於基板11之 其中一面11a而略平行地混合存在並被配置。 例 J 施 例實 施(One or a mixture of two or more selected from the group consisting of SrTi03, Υ203, Η02Ο3, Bi2〇3, Ce02, and Α1203 is preferable, and titanium dioxide fine particles (nanoparticles) are particularly preferable. The average particle diameter of the titanium dioxide is preferably about 2 nm to 100 nm. As the conductive fine particles, conductive particles such as a conductor or a semiconductor are used. The range of the specific resistance of the conductive particles is preferably 1.0 x 1 0 · 2 Ω · cm or less, more preferably 1 · 〇χ 1 〇 _ 3 Ω · cm or less. Further, the type of the conductive particles or the particle size of -18 to 200950106 is not particularly limited, but the electrolyte is condensed by using an ionic liquid as a main component and having excellent compatibility with the electrolyte. Gelatinize the latter. Further, the conductive particles are required to form an oxidized separator (insulating separator) or the like in the electrolyte to lower the conductivity, and the chemical stability is excellent for other coexisting components contained in the electrolyte. . In particular, as the conductive particles, even when the electrolyte contains an iodine/iodide ion or a redox pair such as bromine φ / bromide ion, no oxidation reaction occurs. Deteriorating is ideal. Examples of such a conductive fine particle include a material mainly composed of carbon, and specific examples thereof include particles such as carbon nanotubes, carbon fibers, and carbon black. The manufacturing methods of such materials are well known, and it is also possible to use commercially available sellers. The sealing member 40 is not particularly limited as long as it has excellent adhesion to the substrate 11 constituting the counter electrode 10 or the substrate 21 constituting the working electrode 20, and is a material constituting the sealing member 40, for example, ' Examples thereof include resins such as an ionic polymer, an ethylene-vinyl acetate anhydrous copolymer, an ethylene-methacrylic acid copolymer, an ethylene-vinyl alcohol copolymer, an ultraviolet curable resin, and a vinyl alcohol copolymer. Further, the sealing member 40 may be composed only of a resin, or may be composed of a resin and an inorganic filler. Specific examples of the resin include HIMILAN (manufactured by Mitsui DuPont Chemical Co., Ltd.), NUCREL (manufactured by Mitsui DuPont Chemical Co., Ltd.), and the like. The present invention is not limited to the above embodiment. For example, in the embodiment of the above-mentioned -19-200950106, the counter electrode 10 is provided with the substrate H, but the substrate 11 is not necessarily included. For example, when the intermediate layer 12 can be applied to a substrate and then separated from the substrate as a self-standing film, the counter electrode may be composed of the intermediate layer 12 and the separator 14. Further, in the above embodiment, in the intermediate layer 12, the respective carbon nanotube tubes 13 are arranged such that their longitudinal directions are slightly parallel to one side 11a of the substrate 1 1 and are disposed, but each The carbon nanotube 13' may not necessarily have its longitudinal direction mixed and arranged in parallel with respect to one side 11a of the substrate 11. Example J Example implementation (
(電極基板之製作） 藉由熱CVD法，而製作了平均直徑2nm之單層碳奈 米管。而後，將此單層碳奈米管，與98%硫酸：60%硝酸 爲3: 1之溶液作混合，並進行2小時之超音波處理，而 製作了使單層碳奈米管作了分散之溶液。接著，使用由 PTFE所成之厚度35 # m的濾紙，並對此溶液作過濾，再 在200°C下而使其乾燥並從濾紙而分離，而得到了由單層 碳奈米管所成之膜。進而，在由單層碳奈米管所成之膜處 ，塗布包含有5 wt%之PTFE共聚物（Nafion Dup〇n公司製 )的溶液，並在135°C下使其乾燥，而製作了將由PTFE 所成之厚度5//m的分隔物作了成膜後之電極基板。將此 電極基板，作爲光電變換元件之對電極而使用。 -20- 200950106 (電解質之製作） 對由包含有碘/碘化物離子氧化還原對之離子液體（ 1-乙基-3-甲基咪唑-雙（三氟甲基磺酰）亞胺）所成之電解 液作了調整。 (.作用電極之製作） φ 作爲透明電極基板，使用附有FTO膜之玻璃基板，並 在此透明電極基板之FTO膜（導電層）側的表面上，塗布 平均粒徑20 nm之氧化欽的泥獎狀分散水溶液，並在乾燥 後，在45 0 °C下而進行1小時之加熱處理，藉由此，而形 成了厚度7〆m之氧化物半導體多孔質膜。進而，在釕聯 吡啶錯合物（N3色素）的乙醇溶液中浸漬一晚，而使其 擔持色素，並製作了作用電極。 〇 (胞之製作） 在作用電極與對電極之間注入電解質並作貼合，而作 成了實施例1之太陽電池胞。 (實施例2 ) 在製造對電極時，代替單層碳奈米管，而使用平均直 徑2 Onm之多層碳奈米管，除此之外，與實施例1同樣的 而製作了太陽電池胞。另外，多層碳奈米管，係使用熱 CVD法而製作。 -21 - 200950106 (實施例3 ) 在製造對電極時，代替單層碳奈米管’而使用單層碳 奈米管與多層碳奈米管之混合粉末，除此之外’與實施例 1同樣的而製作了太陽電池胞。另外’作爲多層碳奈米管 ，係使用與實施例2相同者。又，單層碳奈米管與多層碳 奈米管之混合比例，係爲質量比1 : 1。 (實施例4 ) 在製造對電極時，代替單層碳奈米管，而使用碳黑（ KETJEN BLACK INTERNATIONAL 公司製 KETJEN BLACK EC)，除此之外，與實施例1同樣的而製作了太陽電池胞 (實施例5 ) 在製造對電極時，代替單層碳奈米管，而使用單層碳 © 奈米管與碳黑（KETJEN BLACK INTERNATIONAL公司製 KETJEN BLACK EC)之混合粉末，除此之外，與實施例1 同樣的進行製作，並將此作爲實施例5之太陽電池胞。又 ，相對於單層碳奈米管之碳黑的混合比例，係爲質量比1 (實施例6) 在製造對電極時，將分隔物之厚度設爲了 l；/m，除 -22- 200950106 液作混合，並進行2小時之超音波處理，而製作了使單層 碳奈米管作了分散之溶液。接著，使用由PTFE所成之厚 度35gm的濾紙，而對此溶液作過濾，再在2〇〇°c下而使 其乾燥並從濾紙而分離，而得到了由單層碳奈米管所成之 膜。將此膜作爲對電極來使用，除此之外，與實施例1同 樣的而製作了太陽電池胞。 φ (光電變換特性） 對於如同上述一般而製作了的實施例1〜11以及比較 例1之太陽電池胞的光電變換特性作了測定。於表1，展 示此結果。 〔表1〕 光電變換效率（％ ) 未發電之胞的比例（％ ) 實 施 例 1 5 • 1±0 2 1 實 施 例 2 5 ·0±0·1 2 實 施 例 3 5 3±0 2 1 實 施 例 4 3 8±1 0 8 實 施 例 5 4 0±0 6 5 實 施 例 6 5 3±0 7 4 實 施 例 7 5·2±0·3 2 實 施 例 8 5 1±0 5 2 實 施 例 9 5·2±0·3 2 實 胞 网 10 5·0±0·3 1 實 拖 网 11 5 0±0. 5 1 比 較 例 1 4. 7±1 . 5 20 根據表1，在於對電極之中間層中使用有包含碳奈米 管者之實施例1〜11與比較例1中，光電變換效率係爲 -24- 200950106 此之外，與實施例1同樣的而製作了太陽電池胞。 (實施例7) 在製造對電極時，將分隔物之厚度設爲了 3μΐη，除此 之外，與實施例1同樣的而製作了太陽電池胞。 (實施例8 ) 在製造對電極時，將分隔物之厚度設爲了 8μιη，除此 @ 之外，與實施例1同樣的而製作了太陽電池胞。 (實施例9) 在製造對電極時，將分隔物之厚度設爲了 Ιίμηι，除 此之外，與實施例1同樣的而製作了太陽電池胞。 (實施例1 〇 ) 在製造對電極時，將分隔物之厚度設爲了 16μιη ’除 〇 此之外，與實施例1同樣的而製作了太陽電池胞。 (實施例1 1 ) 在製造對電極時’將分隔物之厚度設爲了 20μιη’除 此之外，與實施例1同樣的而製作了太陽電池胞。 (比較例1 ) 將單層碳奈米管，與98%硫酸：60%硝酸爲3 : 1之溶 -23- 200950106 3 8 %以上，而觀察到了高光電變換效率。 (短路了的胞之比例） 接著，各準備100個的上述實施例1〜Η以及比較例 1之太陽電池胞，並對於此些之太陽電池胞中的作用電極 與對電極是否有短路一事作了調查，而對於未發電之胞的 比例作了觀察。於表1，展示此結果。 Φ 根據表1所示之結果，在於中間層處作爲分隔物而配 置了 ΡΤΤΕ的實施例1〜11中，於大部分的胞處係觀察到 有發電。然而，在並未於中間層處作爲分隔物而配置 ΡΤΤΕ的比較例1中，在作用電極與對電極之間產生有短 路之胞係爲多，而在2 0%的胞中係並未引起發電。 由以上可知，係確認了：若藉由本發明，則藉由將包 含有身爲低價且導電性爲高之材料的碳奈米管之多孔質碳 作爲對電極之中間層來使用，且亦使其具備有分隔物，則 ® 能夠實現一種：光電變換效率係爲優良，且難以產生作用 電極與對電極間之短路的光電變換元件。 又，亦確認了：若藉由本發明，則能夠容易地製作太 陽電池胞。 〔產業上之利用可能性〕 本發明，係成爲能夠提供一種能夠實現在光電變換效 率爲優良的同時，亦難以產生作用電極與對電極間之短路 的光電變換元件之對電極、以及具備有該對電極之光電變 -25- 200950106 換元件。 【圖式簡單說明】 〔圖1〕展示本發明之對電極的實施形態之剖面圖。 〔圖2〕展示圖1之對電極的平面圖。 〔圖3〕圖2中之α的擴大圖。 〔圖4〕沿著圖3之Μ-Μ線的剖面圖。 〔圖5〕對於具備有本發明之對電極的光電變換元件 作模式性展示的剖面圖。 【主要元件符號說明】 I 〇 :對電極 II :基板 11a:基板之其中一面 1 2 :中間層 1 2 a ·:中間層之其中一面 13 :碳奈米管 20 :作用電極 21 :基材 22 :透明導電膜 23 :多孔質氧化物半導體層 30 :電解質 40 :密封構件 5 0 :光電變換元件 -26-(Production of Electrode Substrate) A single-layer carbon nanotube having an average diameter of 2 nm was produced by a thermal CVD method. Then, the single-layer carbon nanotube tube was mixed with a solution of 98% sulfuric acid: 60% nitric acid in a ratio of 3:1, and ultrasonic treatment was performed for 2 hours to prepare a single-layer carbon nanotube. Solution. Next, a filter paper having a thickness of 35 # m made of PTFE was used, and the solution was filtered, dried at 200 ° C and separated from the filter paper to obtain a single-layer carbon nanotube. The film. Further, a solution containing 5% by weight of a PTFE copolymer (manufactured by Nafion Dup Co., Ltd.) was applied to a film formed of a single-layer carbon nanotube, and dried at 135 ° C to prepare a film. A separator having a thickness of 5/m made of PTFE was used as an electrode substrate after film formation. This electrode substrate was used as a counter electrode of a photoelectric conversion element. -20- 200950106 (Preparation of Electrolyte) For the ionic liquid (1-ethyl-3-methylimidazole-bis(trifluoromethylsulfonyl)imide) containing an iodine/iodide ion redox pair The electrolyte was adjusted. (Production of the working electrode) φ As the transparent electrode substrate, a glass substrate with an FTO film was used, and on the surface of the FTO film (conductive layer) side of the transparent electrode substrate, an oxidized crystal having an average particle diameter of 20 nm was applied. The aqueous solution was dispersed in a mud-like shape, and after drying, it was subjected to heat treatment at 45 ° C for 1 hour, whereby an oxide semiconductor porous film having a thickness of 7 μm was formed. Further, the mixture was immersed in an ethanol solution of a ruthenium pyridine complex (N3 dye) for one night to carry a dye, and a working electrode was produced. 〇 (Production of Cell) A solar cell of Example 1 was fabricated by injecting and bonding an electrolyte between the working electrode and the counter electrode. (Example 2) A solar cell was produced in the same manner as in Example 1 except that a multilayer carbon nanotube having an average diameter of 2 Onm was used instead of the single-layer carbon nanotube. Further, a multilayer carbon nanotube was produced by a thermal CVD method. -21 - 200950106 (Example 3) In the production of a counter electrode, a mixed powder of a single-layer carbon nanotube and a multilayer carbon nanotube was used instead of a single-layer carbon nanotube', except for 'with Example 1 The solar cells were made in the same way. Further, as the multilayer carbon nanotube, the same as in the second embodiment was used. Further, the mixing ratio of the single-layer carbon nanotubes to the multilayer carbon nanotubes is a mass ratio of 1:1. (Example 4) A solar cell was produced in the same manner as in Example 1 except that a carbon black (KETJEN BLACK EC manufactured by KETJEN BLACK INTERNATIONAL Co., Ltd.) was used instead of the single-layer carbon nanotube. Cell (Example 5) In the production of the counter electrode, instead of a single-layer carbon nanotube, a mixed powder of a single-layer carbon nanotube tube and carbon black (KETJEN BLACK EC, manufactured by KETJEN BLACK INTERNATIONAL) was used. The same procedure as in Example 1 was carried out, and this was taken as the solar cell of Example 5. Further, the mixing ratio of carbon black to the single-layer carbon nanotube is a mass ratio of 1 (Example 6). When manufacturing the counter electrode, the thickness of the separator is set to 1; / m, except -22-200950106 The liquid was mixed and subjected to ultrasonic treatment for 2 hours to prepare a solution in which a single-layer carbon nanotube was dispersed. Next, using a filter paper having a thickness of 35 gm made of PTFE, the solution was filtered, dried at 2 ° C and separated from the filter paper to obtain a single-layer carbon nanotube. The film. A solar cell was produced in the same manner as in Example 1 except that the film was used as a counter electrode. φ (photoelectric conversion characteristic) The photoelectric conversion characteristics of the solar cell of Examples 1 to 11 and Comparative Example 1 which were produced as described above were measured. In Table 1, this result is shown. [Table 1] Photoelectric conversion efficiency (%) Ratio of cells not generated (%) Example 1 5 • 1±0 2 1 Example 2 5 ·0±0·1 2 Example 3 5 3±0 2 1 Implementation Example 4 3 8±1 0 8 Example 5 4 0±0 6 5 Example 6 5 3±0 7 4 Example 7 5·2±0·3 2 Example 8 5 1±0 5 2 Example 9 5 ·2±0·3 2 Cellular network 10 5·0±0·3 1 Real trawling 11 5 0±0. 5 1 Comparative example 1 4. 7±1 . 5 20 According to Table 1, the middle layer of the counter electrode In Examples 1 to 11 and Comparative Example 1 in which carbon nanotubes were used, solar cell cells were produced in the same manner as in Example 1 except that the photoelectric conversion efficiency was -24 to 200950106. (Example 7) A solar cell was produced in the same manner as in Example 1 except that the thickness of the separator was changed to 3 μm. (Example 8) A solar cell was produced in the same manner as in Example 1 except that the thickness of the separator was set to 8 μm. (Example 9) A solar cell was produced in the same manner as in Example 1 except that the thickness of the separator was changed to Ιίμηι when the counter electrode was produced. (Example 1 太阳) A solar cell was produced in the same manner as in Example 1 except that the thickness of the separator was changed to 16 μm. (Example 1 1) A solar cell was produced in the same manner as in Example 1 except that the thickness of the separator was changed to 20 μm. (Comparative Example 1) A single-layer carbon nanotube was mixed with 98% sulfuric acid: 60% nitric acid to a ratio of 3:1 to -23-200950106 3 8 % or more, and high photoelectric conversion efficiency was observed. (Proportion of short-circuited cells) Next, 100 solar cells of the above-described Examples 1 to Η and Comparative Example 1 were prepared, and whether or not the working electrode and the counter electrode in the solar cell were short-circuited The survey was conducted and the proportion of unpowered cells was observed. In Table 1, this result is shown. Φ According to the results shown in Table 1, in Examples 1 to 11 in which ruthenium was disposed as a separator at the intermediate layer, power generation was observed in most of the cells. However, in Comparative Example 1 in which ruthenium was not disposed as a separator at the intermediate layer, a cell line having a short circuit between the working electrode and the counter electrode was excessive, and was not caused in 20% of the cells. Power generation. As described above, it has been confirmed that, according to the present invention, porous carbon containing a carbon nanotube having a material which is low in cost and high in conductivity is used as an intermediate layer of a counter electrode, and When it is provided with a separator, it is possible to realize a photoelectric conversion element in which the photoelectric conversion efficiency is excellent and it is difficult to generate a short circuit between the working electrode and the counter electrode. Further, it has been confirmed that the solar cell can be easily fabricated by the present invention. [Industrial Applicability] According to the present invention, it is possible to provide a counter electrode of a photoelectric conversion element which is excellent in photoelectric conversion efficiency and which is unlikely to cause a short circuit between a working electrode and a counter electrode, and Optoelectronics of the electrode -25- 200950106 Replace the components. BRIEF DESCRIPTION OF THE DRAWINGS [Fig. 1] A cross-sectional view showing an embodiment of a counter electrode of the present invention. Fig. 2 is a plan view showing the counter electrode of Fig. 1. [Fig. 3] An enlarged view of α in Fig. 2. [Fig. 4] A cross-sectional view taken along line Μ-Μ of Fig. 3. Fig. 5 is a cross-sectional view schematically showing a photoelectric conversion element having a counter electrode of the present invention. [Description of main component symbols] I 〇: counter electrode II: substrate 11a: one side of the substrate 1 2 : intermediate layer 1 2 a · one side of the intermediate layer 13 : carbon nanotube 20 : working electrode 21 : substrate 22 : Transparent Conductive Film 23 : Porous Oxide Semiconductor Layer 30 : Electrolyte 40 : Sealing Member 5 0 : Photoelectric Conversion Element -26-